How long will the HDD keep working?



It is well known that HDDs have a limited lifespan and can eventually break after many years of use. Backblaze, which publishes HDD failure rate statistics every year, picked up 10 types of HDDs used in its own data center and calculated the failure rate in order to find out how many years the HDD will operate.

Hard Drive Life Expectancy

https://www.backblaze.com/blog/hard-drive-life-expectancy/

Backblaze sets out the annual failure rate of HDDs every year, but this time we changed the viewpoint and calculated the 'lifetime' of HDDs. 'For example, it is academically interesting to know that the annual failure rate of a washing machine is 4%, but what we really want to know is,'How long can we expect to have a new washing machine?' That's what it is, 'he said, applying this to HDDs and collecting statistics.

The HDDs picked up by Backblaze were 10 models made by Seagate, HGST, and Toshiba, and were compared by dividing them into 4 types: 4TB, 8TB, 12TB, and 14TB. In addition to the statistics, the Kaplan-Meier curve shows the expected occupancy rate for each elapsed month. Backblaze refers to its own data from 2013 to 2022.

◆ 4TB
The record of 4TB HDD is as follows. The following two models are said to have been the most numerous 4TB models as of March 31, 2022.
Manufacturer model Number of operations Number of lifetime failures Lifetime working days Lifetime annual failure rate
HGST HMS5C4040BLE640 12,728 343 3,025,871 0.40%
Seagate ST4000DM000 18,495 4581 68,104,520 2.45%


The graph is below. If you use the HGST model from a new state, there is a 97% chance that it will continue to work after 72 months, and if you use the Seagate model from a new state, there is an 81% chance that it will continue to work after 72 months. is showing.



Backblaze said, 'Case closed. It was stupid to buy a Seagate 4TB model.'

◆ 8TB
The record of 8TB is below. The upper 'ST8000DM002' is for consumers, and the lower 'ST8000NM0055' is for enterprises.

Manufacturer model Number of operations Number of lifetime failures Lifetime working days Lifetime annual failure rate
Seagate ST8000DM002 9678 628 1981 55919 1.13%
Seagate ST8000NM0055 14,323 915 24,999,738 1.35%


The graph looks like this. Approximately 95% of consumer models and 93.6% of enterprise models will continue to operate five years after they are first used.



Backblaze said, 'Both HDDs worked well. If you want to buy an 8TB model and a sales person says,'There's a 93.6% chance that it'll still work in five years,' that's a pretty good number. '.

◆ 12TB

Manufacturer model Number of operations Number of lifetime failures Lifetime working days Lifetime annual failure rate
HGST HUH721212ALN604 10,0813 148 11813149 0.48%
Seagate ST12000NM001G 12,269 104 6,166,144 0.63%
Seagate ST12000NM0008 20,139 449 1480,25277 1.12%


As shown in the graph below, it can be expected that at least 98% of all three models can be used continuously for two years.



◆ 14TB

Manufacturer model Number of operations Number of lifetime failures Lifetime working days Lifetime annual failure rate
Toshiba MG07ACA14TA 38,210 454 1983,84886 0.83%
Seagate ST14000NM001G 10,734 one two three 4,474,417 1.00%
WDC WUH721414ALE6L4 8268 35 3,941,427 0.33%


All three models were up and running at 99% one year after they were first used. Backblaze pointed out that the failure rate graph over time should normally draw

a bathtub-like curve
, but the Toshiba model has a failure rate one point higher than previously predicted after 36 months.



in Hardware, Posted by log1p_kr